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81.
Water hyacinth was the chosen alternative biomass for H2 production in this study. A batch and a continuous pilot plant systems are proposed. A batch system of 500?ml capacity was developed first for finding an appropriate biomass ratio which was found to be 2.5%wt. Results from the batch system was used to construct a kinetic model of water hyacinth hydrolysis. The same biomass and water ratio was used in the continuous system. Besides water hyacinth, glucose and cellulose?+?lignin biomasses were tested. During processing, temperature, pressure, and electric consumption of the system were recorded. The quality and quantity of gas products were analyzed by gas chromatography (GC). The water hyacinth biomass attained the highest rate of H2 production (providing energy of 11.43?kWh/mole of glucose). Comparing the batch and continuous pilot systems, the continuous system achieved 2.7 times more H2 mole% than the batch system did. 相似文献
82.
目的 考察蔓越莓中膳食纤维的结构性质和功能性质。方法 利用酶解法提取蔓越莓总膳食纤维、不溶性膳食纤维和可溶性膳食纤维, 并采用红外光谱和高效液相色谱测定其官能团结构和分子量, 采用质构仪和粘度计测定其凝胶性质和粘度, 同时对膳食纤维吸附亚硝酸根离子、交换阳离子、胆固醇、重金属和葡萄糖的能力进行研究。结果 总膳食纤维和不溶性膳食纤维的提取率较高, 分别为54.67%和38.70%, 膳食纤维具有凝胶和粘度的性质, 同时在功能上有吸附亚硝酸根离子, 交换阳离子, 吸收胆固醇, 重金属离子和葡萄糖的性能。结论 蔓越莓膳食纤维具有特殊的结构性质和很好的功能活性, 可以开发蔓越莓新功能食品。 相似文献
83.
S. M. Mahfuzul Islam Abdullah A. Loman Qian Li Lu-Kwang Ju 《Journal of the American Oil Chemists' Society》2020,97(9):963-975
The enzymatic treatment of defatted soy flour (SF) to reduce indigestible carbohydrates can result in undesirable protein loss. Here protein loss was minimized with quantitation of the effects of ionic strength (IS), protease activity, and SF toasting. At the enzyme processing condition (25% w/v SF, 50 °C, pH 4.8, 48 hours), protein loss increased linearly with the IS in enzyme broths (EB); e.g., contacting untoasted SF with water or heat-deactivated EB showed protein loss of 28% in water but up to 40% when IS was increased in the range of 0.04–0.19 M. Protein loss also increased with protease in EB (nondeactivated): after adjusted for IS-related loss, approximately 10% and 25% additional protein loss occurred in EB of 73 and 490–557 U/(g SF) protease, respectively. SDS-PAGE results showed that proteolysis was not extensive, mainly on β-conglycinin α'/α and glycinin acidic 37-kDa subunits; and most of the proteolytic products could be recovered by heat-induced precipitation. SF toasting effects were studied, particularly at 2-hours 160°C, with material balances, protein distributions, and monosaccharide yields in hydrolysates. Overall, protein loss was minimized to 5.2% and the conversion of carbohydrate to monomeric sugars increased to 89.2%. 相似文献
84.
以2-苄基吡啶氮氧化物和三氟乙酸酐为原料,通过“一锅三步法”(串联“酰化、[3,3]σ重排和水解”反应)合成了关键药理活性中间体苯基-2-吡啶基甲醇,并对反应条件进行了优化。结果表明:当n(2-苄基吡啶氮氧化物):n(三氟乙酸酐)=1 : 1.2、N, N-二异丙基乙胺(DIPEA)为碱、甲苯为反应溶剂,室温反应6小时,经硅胶柱层析分离即可得到苯基-2-吡啶基甲醇,收率为81.0%。产物经1H NMR,13C NMR 和HRMS进行结构表征。本文以原子经济学的理念首次实现了由2-苄基吡啶氮氧化物到苯基-2-吡啶基甲醇的直接转化。 相似文献
85.
86.
An investigation was conducted into the generation of hydrogen from catalytic hydrolysis of alkaline sodium borohydride solution in a micro-scale fluidized bed. In this work, the Cobalt loaded on walnut shell activated carbon was applied as the catalyst. The impact of NaBH4 concentration, the diameter of catalyst particle, the rate of reaction fluid flow, and the temperature of initial reaction fluid on the process of hydrogen generation was explored, and the optimum reaction conditions were determined. It was found out that the maximum length of stable hydrogen generation (58.46% of the total reaction time) is obtainable under the following conditions. The concentration of NaBH4 is 2 wt%, the flow rate is 3.00 × 10−3 m·s−1, and the flow temperature is 25°C. In addition, a comparison was performed between the batch reactor and micro-fluidized bed reactor during the process of hydrogen generation. Moreover, when the concentration of NaBH4 reached 1 and 2 wt%, the efficiency and stability of the micro-fluidized bed reactor were identified as superior to those of the batch reactor. 相似文献
87.
88.
Corn stover was pretreated with dilute sulfuric acid to test the interaction effects of pH, cellulase loading and β-glucosidase loadings on biomass hydrolysis rates. A response surface model was developed showing that β-glucosidase supplementation had limited practical impact on hydrolysis between 0.5 and 2 CBU FPU−1. The only significant interaction in the model was between pH and β-glucosidase loading but it also had little practical significance. Corn stover and corn cob were used to test the effects of further β-glucosidase reduction. Significant hydrolysis improvements were seen when 0.2 CBU FPU−1 were added but very little improvement was seen for higher loadings. Residual cellobiose concentrations confirmed these findings but suggest that further reductions would have more noticeable negative effects on hydrolysis rates. Results show that β-glucosidase supplementation during biomass hydrolysis can be reduced to between 10% and 20% of typical loadings. 相似文献
89.
Current study investigated the potential to increase the activity of α-L-arabinofuranosidase (TmAra) from Thermotoga marotima on insoluble arabinoxylan (IAX) through fusion to a family 6 xylan-binding domain (CtXBD6) from Clostridium thermocellum. CtXBD6 was fused to the carboxyl terminus of TmAra, and active forms of both TmAra and TmAraCtXBD6 were produced in E. coli and purified to homogeneity for biochemical characterization. TmAraCtXBD6 had similar temperature and pH profiles to TmAra with a decrease in the thermostability and pH stability at pH 7.0–8.2. It exhibited stronger IAX-binding and hydrolytic activity than TmAra. TmAra and TmAraCtXBD6-treated IAX were added to wheat flour to investigate the rheological and textural properties of the finished product. IAX alone had significant increase in dough development time (DDT) and dough stability (DS) and decrease in the softening degree (SD), crumb firmness (CF) and specific volume (SV). On adding TmAra and TmAraCtXBD6 to treat IAX texture, SV and DS improved but decreased DDT, SD, and CF. TmAraCtXBD6 reduced CF and increased SV, and had higher springiness, cohesiveness, and crumb chewiness than TmAra. These results demonstrated that the fusion of CtXBD6 into arabinofuranosidase enables the increase in catalytic performance on insoluble AX substrates, which can be used as more efficient biocatalysts that can improve the quality of AX-rich products. 相似文献